Fig. 11. Shading indicates the mass fraction of CO₂ in the gas phase and labeled contour lines indicate the water saturation for the case of zero leakage and an initial CO₂ plume present in the unsaturated zone. (a) t = 6 mo, (b) t = 1 yr, (c) t = 5 yr, and (d) t = 10 yr. The maximum vector size represents a value of approximately (a) 2.8 x 10^-2, (b) 2.0 x 10^-2, (c) 7.5 x 10^-3, and (d) 3.9 x 10^-3 m d^-1.